The present invention relates to a semimoist process copier which electrostatically forms a latent image on a photoconductive element and develops it by a liquid developer and, more particularly, to a semimoist process copier capable of starting on a copying operation immediately and thereby reducing a waiting time.
A semimoist process copier includes a cleaning blade made of rubber or similar elastic material for cleaning the surface of a photoconductive element after the transfer of a developed image from a photoconductive element to a paper sheet. Specifically, the cleaning blade is pressed against the photoconductive element to remove a remaining liquid developer off the photoconductive element. If the cleaning blade is pressed against the photoconductive element at all times, the former is apt to deform or otherwise damage the latter. In the light of this, it is a common practice to release the cleaning blade from the photoconductive element on the lapse of a predetermined period of time after a copying operation has been ended. Generally, the release of the cleaning blade from the photoconductive element is effected in response to the switchover of the copier from a copy mode in which it is ready to operate to either one of a power off mode and a preheat mode. In the power off mode the power source of the copier is turned off, while in the preheat mode only the display section on the operation board of the copier is turned off. Such switchover of operating mode is adopted for a power saving purpose also. In practice, the switchover occurs automatically when 1 minute or 15 minutes, for example, expires since the end of a copying operation. When the power source is turned on again or a preheat mode cancel key is pressed in order to resume the copying operation while the power off mode or the preheat mode is set up, the cleaning blade is caused into pressing contact with the photoconductive element. Then, the cleaning blade precleans the photoconductive element to remove contamination which occurred when the cleaning blade was released at the end of the previous copying operation. Specifically, the photoconductive element is rotated with the liquid developer being fed from a cleaning unit onto the photoconductive element for a predetermined period of time.
As stated above, the prior art semimoist process copier cannot resume a copying operation on the lapse of a predetermined period of time after the previous operation, unless one turns on the power source again, cancels the preheat mode or otherwise triggers the copier. Moreover, after such a triggering manipulation, one has to simply wait until the photoconductive element has been throughly precleaned, i.e., one cannot operate the machine until a precleaning time expires. Therefore, it may occur that the operator regards the copier as having failed and therby gives up using it due to the turn-off of the power source or that of the display section.